BAGHDAD (AP) — Two bombs including a suicide attack on a cafe killed 21 people in central Iraq on Monday evening, officials said. They were the latest attacks in a months-long surge of violence.

In the deadlier blast, a suicide bomber detonated his explosive belt inside a cafe in Balad, 80 kilometers (60 miles) north of Baghdad, killing 15 people and wounding another 30, police said. Militants frequently attack Shiite civilian targets to undermine the government.

About two hours later, six people were killed and 17 others wounded in a bomb explosion near a restaurant in the city of Baqouba, 60 kilometers (35 miles) northeast of Baghdad.

Two medical officials in a nearby hospital confirmed the casualty figures. All officials spoke on condition of anonymity as they were not authorized to talk to journalists.

The latest surge in violence has raised fears that Iraq could be returning to widespread sectarian killings similar to those that brought the country to the edge of civil war in 2006 and 2007.

Meanwhile, Al-Qaida’s branch in Iraq claimed responsibility for attacks that killed 69 people during the Muslim holiday following the end of the holy month of Ramadan.

Last Saturday’s attacks targeted mostly cafes and busy marketplaces. They were part of a wave of bloodshed that has swept Iraq since April, killing more than 3,000 people and worsening already strained ties between Iraq’s Sunni minority and the Shiite-led government.

The Islamic State of Iraq and the Levant — as Iraq’s al-Qaida affiliate is known — said in a statement on the Internet that the bombings were in retaliation for the arrests of hundreds of Muslims by Iraqi security forces.

The authenticity of the statement could not be independently confirmed but it appeared on a website commonly used by militants.